Pre-operative Screening: Early Identification of Patients at Risk for Delirium in Cardiac Surgery. Rima Styra MD, MEd, FRCPC University of Toronto

Transcription

1 Pre-operative Screening: Early Identification of Patients at Risk for Delirium in Cardiac Surgery Rima Styra MD, MEd, FRCPC University of Toronto

2 Preoperative risk factors of POD in cardiac surgery 196 papers reviewed 123 risk factors were identified Age: significant across 47 independent studies Cognitive impairment: significant in 21 independent studies Previous TIA/Stroke: significant in 9 studies Emotional/Personality traits (which included depression): significant in 17 studies Substance use (street drugs, alcohol, nicotine): significant in 7 studies Hollinger, J Cardiothoracic Vascular Anesthesia, 2015

3 Increasing age 47 studies Variable Method of Identification 1 1. General cut-off point: 65 years and older 2. By decade: >=60 2 >=65 3,4 >= ,000 patients - every decade of age starting 50 years old or older : 12%, 28% and then 40% By year: Meta-analysis of risk ratios found the risk rises 8% each year 1 1.Lin, J Car Surgery, Katznelson, Anesthesiol, Kazmierski, J Psychosom Res, Tse,Cardiothor Vasc Anes Koster, European J Cardiovascular Nursing Bucerius, J Thorac Cardiovasc Surg 2004.

4 Cognitive Impairment Author Odds Ratio 95% C.I. P value Banach to 28.6 p< Kazmierski to p<0.001 Schoen to p=0.018 Koster to 12.7 p=0.004 Tse to 4.9 p=0.006 Banach, Med Sci Monitor, 2008; Kazmierski, J Psychosom Research 2010 ; Schoen, Critical Care 2010; Koster, Eur J Cardiovas Nurs 2013; Tse, J Cardiothor Vasc Anes 2015

5 Limitations of cognitive impairment research Measurement tools used were not consistent and in one case the instrument was not identified, nor the method of diagnosis MMSE cut off points for defining cognitive impairment varied throughout the studies Inclusion/exclusion of dementia patients from studies changes prevalence rate of impairment

6 Depression Few of the studies use scales Past history chart review Self-report Odds ratios: to Rudolph, Circulation, Banach, Med Sci Monitor, 2008

7 Patient population UHN is a tertiary care hospital with 28 CVICU beds and 40 cardiac surgery beds Patients waiting for surgery were identified in the pre-operative clinic based on risk factors Some of the risk factors that were highlighted: - documented, self or family report of cognitive issues - history of cerebrovascular accident or TIA - psychiatric history - substance use Cardiac surgery patients were referred for preoperative psychiatric assessment which occurred at the time of the pre-operative assessment

8 Assessed variables Psychiatric diagnosis (based on a psychiatric assessment by a CL psychiatrist) using DSM IV TR/DSM 5 criteria MMSE scores pre-operatively for all patients Cognitive impairment (defined as MMSE score of 24) Heavy alcohol use: (based on Canadian guidelines) >10 drinks per week (female) >15 drinks per week (male) Benzodiazepine use as per lorazepam equivalents Substance use disorder versus occasional use

9 Patient follow-up Psychiatrist followed up on patients seen pre-op within hours of surgery (exception: patients who had surgery on Friday, followed up on the Monday) Nursing staff in the CVICU complete delirium rating scales NEECHAM originally and then hospital adopted the CAM-ICU and CAM on the floor completed once every shift Three sources of assessment for delirium nursing, scales and psychiatrist

10 Methods 421 patients were originally assessed 26 patients not included (6 patients passed away during surgery or declined surgery; 20 patients did not complete the MMSE) Patients were seen prospectively with retrospective chart review of 395 preoperative psychiatric consultation records and post-operative notes of patients

11 Proportion of sample assessed by delirium tool Tool Sample size Percentage (%) NEECHAM % CAM %

12 Prevalence of risk factors by gender Overall delirium rate: 26.1% Total N=395 Males N = 227 ( 57.7%) Females N = 168 (42.5 %) Delirium 57 (25.1%) 46 (27.4%) History of CVA/TIA 75 (33%) 52 (31%) Heavy users of alcohol 13 (5.7%) 14 (8.3%) Currently uses substances 7 (3.1%) 5 (3%) Current depression 40 (17.6%) 51 (30.4%)

13 Prevalence of delirium by cardiac surgery type Surgery Type Non-Delirious N=292 Delirious N=103 OR (95% CI) P value ACB 99 (22.9%) 31 (30%) 0.84 ( ) P=0.48 ACB + Valve 24 (8.2%) 19 (18.4%) 2.52 ( ) P=0.02 Valve 150 (41.3%) 51 (49.5%) 1.08 ( ) P=0.74

14 Results Variable Mean Age (years) Cohort Non-Delirious N=292(%) Delirious N=103(%) OR (95% CI) P value n/a *p< years 44 (15%) 35 (34.3%) 2.96 ( ) *p< years 81 (27.6%) 33 (32.3%) 1.25 ( ) p= years 78 (26.7%) 24 (23.3%) 0.83 ( ) p= years 56 (19.1%) 10 (9.8%) 0.46 ( ) p=0.014

15 Results Variable Mean MMSE score (Range) Non-Delirious N=292 (%) Delirious N=103 (%) OR (95% CI) P value 26.9 (14-30) 25.7 (17-30) n/a *p= MMSE (17.8%) 33 (32%) Depression 32 (10.9%) 9 (8.8%) CVA/TIA 89 (30.1%) 38 (37.3%) Heavy alcohol use 22 (7.5%) 5 (4.7%) 2.18 ( ) 0.79 ( ) 1.36 ( ) 0.63 ( ) *p=0.006 p=0.533 p=0.213 p=0.33

16 Other Psychiatric Disorders Patients with anxiety diagnosis : - panic disorder 4% - generalized anxiety disorder 3% Anxiety diagnosis (p=0.241) was nonsignificant as a risk factor for delirium Schizophrenia numbers too low

17 Risk Factor Results Variable OR (95% CI) P value Age 65 years 3.79 ( ) p< High benzodiazepine use (>2 mg lorazepam equiv) 3.56 ( ) p=0.009 Previous delirium 2.71 ( ) p=0.012 Cognitive impairment 2.49 ( ) p=0.006

18 Independent OR comparison Citation/Author Age 65 (95% CI) Previous delirium Cognitive impairment Tse ( ) 7.7 ( ) 2.5 ( ) Kazmierski ( ) N/A 6.14 ( ) Koster 2013 N/A 5.5*** ( ) 4.5 ( ) Styra ( ) 2.71 ( ) 2.49 ( ) ***p=0.07 Tse, J Cardiothoracic Vascular Anesthesia 2015 Kazmierski, J Psychosomatic Research 2010 Koster, European J Cardiovascular Nursing 2013

19 Over-representation of CVA/TIA Citation/Author Delirium % Non Delirium % CVA/N sample CVA/N sample % Tse /679 5 Kazmierski / Bucerius /16, Koster / Guenther / Katznelson / Styra / Tse, J Cardiothoracic Vascular Anesthesia 2015 Kazmierski, J Psychosomatic Research 2010 Bucerius, J Thoracic Cardiovascular Surgery 2004 Koster, European J Cardiovascular Nursing 2013 Guenther, Annals Surgery 2013 Katznelson, Anesthesiology, 2009

20 Heavy alcohol and substance use History of heavy alcohol use by males and females (p=0.207) was not significant, as was street drug use 82% - the majority of heavy alcohol users did not develop delirium This may be due to: - younger mean average age of 51.3 years - lower percentage of cognitive impairment (12%) Early identification of this issue and proper treatment initiated postoperatively (CIWA) Substance use (street drugs and/or alcohol) comorbidity with current or past history of psychiatric disorders was not significant

21 Limitations Cardiac database was based on patients who were referred for psychiatric consultations and as such had larger numbers of patients with mental illness and neurological complications

22 Conclusions Age, cognitive impairment, high use of benzodiazepines, previous delirium were found as the most significant preoperative indicators. This is consistent with other studies Even among high risk patients with high prevalence of depression and history of CVA/TIA, age and cognitive impairment continue to be the two consistent risk factors. Cognitive screening among older patients would provide a signal for concern

23 Conclusions (continued) Results of prediction would be improved by more extensive and specific cognitive testing Preoperative screening for risk merits routine inclusion in pathways of care for cardiac patients A focus on modifiable factors is important Highly complicated preventive strategies likely to fail

24 Acknowledgements Elisabeth Larsen Nizanthan Rathitharan

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26 References Banach, M., Kazmierski J., Kowman, M., Okonski, P., Sobow, T., Kloszewska, I., Jaszewski, R. (2008). Atrial fibrillation as a nonpsychiatric predictor of delirium after cardiac surgery: A pilot study. Medical Science Monitor, 14(5) Bucerius, J., Gummert J. F., Borger, M. A, Walther, T., Doll, N., Falk, V., Mohr, F. W. (2004). Predictors of delirium after cardiac surgery delirium: effect of beating-heart (off-pump) surgery. The Journal of Thoracic and Cardiovascular Surgery, 127(1) Guenther, U., Theuerkauf, N., Frommann, I., Brimmers, K., Malik, R., Stori, S., Popp, J. (2013). Predisposing and precipitating factors of delirium after cardiac surgery. Annals of Surgery, 257, Hollinger, A., Siegemund, M., Goettel, N., Steiner, L. A. (2015). Postoperative delirium in cardiac surgery: An unavoidable menace? Journal of Cardiothoracic and Vascular Anesthesia, 29(6) /j.jvca Inouye, S.K., van Dyck C. H., Alessi, C. A., Balkin, S., Siegal, A. P., Horwitz, R. I. (1990). Clarifying confusion: the Confusion Assessment Method. Annals of Internal Medicine, 113(12), Katznelson, R., Djaiani, G. N., Borger, M. A., Friedman, Z., Abbey, S. E., Fedorko, L., Beattie, W. S. (2009). Preoperative use of statins is associated with reduced early delirium rates after cardiac surgery. Anesthesiology, 110, Kazmierski, J., Kowman, M., Banach, M., Fendler, W., Okonski, P., Banys, A, Kloszewska, I. (2010). Incidence and predictors of delirium after cardiac surgery: Results from the IPDACS study. Journal of Psychosomatic research, 69,

27 References (continued) Koster, S., Hensens, A. G., Schuurmans, M. J., van der Palen, J. (2011). Risk factors of delirium after cardiac surgery: a systematic review. European Journal of Cardiovascular Nursing, 10, Lin, Y., Chen, J., Wang, Z. (2012). Meta-analysis of factors which influence delirium following cardiac surgery. Journal of Cardiac Surgery, 27, Schoen, J., Meyerrose, J., Paarmann, H., Heringlake, M., Hueppe, M., Berger, K-U. (2010). Preoperative regional cerebral oxygen saturation is a predictor of postoperative delirium in on-pump cardiac surgery patients: a prospective observational trial. Critical Care, 15:R218 Tse, L, Schwarz, S. K. W., Bowering, J. B., Moore, R. L., Barr, A. M. (2015). Incidence of and risk factors for delirium after cardiac surgery at a quaternary care center: a retrospective cohort study. Journal of Cardiothoracic and Vascular Anesthesia, 29(6), /j.jvca

28 Preoperative risk factors of POD in cardiac surgery Meta-analysis of 9 studies between Following variables were significant: Age: -every year(four studies) -by decade (two studies) -65 years and older (three studies) History of CVA(four studies) Depression (six studies) Lin, J Cardiac Surgery, 2012

29 Independent Odds Ratio for Depression Delirium (N=190) Prevalence of Depression Non-delirium (N=489) P value 27% (14) 30% (6) P= Lin, 2012 Odds ratio 3.3 [95% CI: ] p<0.001, falling in the range of Lin 2012 s results Tse, J Cardiothoracic Vascular Anesthesia 2015

30 Delirium risk related to drugs and alcohol Hollinger 2015 s systematic review of 132 papers did not find any risk factors associated with alcohol Chang 2008: combined prolonged drug abuse with psychological disorders such as depression, significant only at univariate level, not multivariate level Koster 2013: Heavy alcohol use raised risk by 10.8, with a 95% CI: , p=0.003 Hollinger, J Cardiothoracic Vascular Anesthesia, 2015 Chang, American J Critical Care, 2008 Koster, European J Cardiovascular Nursing 2013